diff --git a/packages/common/http/src/request.ts b/packages/common/http/src/request.ts
index bb49113b0ad71..619f6ed1f7c47 100644
--- a/packages/common/http/src/request.ts
+++ b/packages/common/http/src/request.ts
@@ -324,7 +324,7 @@ export class HttpRequest<T> {
     }
     // Arrays, objects, and numbers will be encoded as JSON.
     if (typeof this.body === 'object' || typeof this.body === 'number' ||
-        Array.isArray(this.body)) {
+        typeof this.body === 'boolean' || Array.isArray(this.body)) {
       return 'application/json';
     }
     // No type could be inferred.
diff --git a/packages/common/http/test/request_spec.ts b/packages/common/http/test/request_spec.ts
index 7519b47e00479..9a0d91f3cac29 100644
--- a/packages/common/http/test/request_spec.ts
+++ b/packages/common/http/test/request_spec.ts
@@ -129,6 +129,10 @@ const TEST_STRING = `I'm a body!`;
         const req = baseReq.clone({body: {data: 'test data'}});
         expect(req.detectContentTypeHeader()).toBe('application/json');
       });
+      it('handles boolean as json', () => {
+        const req = baseReq.clone({body: true});
+        expect(req.detectContentTypeHeader()).toBe('application/json');
+      });
     });
     describe('body serialization', () => {
       const baseReq = new HttpRequest('POST', '/test', null);